I did not know this happened on 9/11, i probably should have.
“The Battle of Vienna took place on 11 and 12 September 1683 after Vienna had been besieged by the Ottoman Empire for two months. It was a battle of the Holy Roman Empire in league with the Polish- Lithuanian Commonwealth (Holy League) versus the Ottoman Empire and chiefdoms of the Ottoman Empire, and took place at the Kahlenberg mountain near Vienna. The battle marked the beginning of the political hegemony of the Habsburg dynasty in the Holy Roman Empire and Central Europe.
The victory at Vienna set the stage for Prince Eugene of Savoy’s reconquering of Hungary and (temporarily) some of the Balkan lands within the following years. The Ottomans fought on for another 16 years, losing control of Hungary and Transylvania in the process, before finally giving up. The Holy Roman Empire signed the Treaty of Karlowitz with the Ottoman Empire in 1699.